Mercury or other vapor electric lamp.



H. A. KENTKz H. G. LACHLL. MERCURY OR OTHER VAPOR. ELECTRIC LAMP.

APPLICATION FILED OUT'. 3,1908.

Patented May 25, 1909.,

INVENTORS 2 ATTORNEYS f UNITED STATES PATENT OFFICE.

.IlENRY ANDREW h-ENT, F BOUNDS GREEN, AND HAROLD GEORGE LACELL, OF FINCHLEY, ENGLAND, ASSIGNORS 'lO SILItA SYNDICATE LIMITED, OF LONDON, ENGLAND.

. suitable substances or compounds which will fill the said tube, andwhen "the lamp is MERCURY on ems varon ELECTRIC LAMP.

no. 023,124. I

' Application filed October a,

To all whom it may concern I Be it dmown that warlinnar ANDREW KENT, a subject of the King of Great Britain, residing at The Poplars Maidstone road, Bounds Green, in the county of Middlesex, England, engineer, and HAROLD. GEORGE LACELL, a subject' of the King of Greati Britain, residing at Ardoch, Nether street, 1 Finchley, inthe said county of Middlesex, En land, chemist, have invented new and i use 1 Improvements in Mercury or other Yapor Electric Lamps, of which the follow-. 1 is aspecification;

his invention has for its object to provide mercury, or other metallic vapor lamps which are simpler and more economical in construction, and .more convenientin, use than are such lamps as hithertomade, the lamps in' accordance with this invention being made so thatthere is no'necessity for the seals and vacuum hitherto necessaryin mercur and-other vapor lamps. ,1 a

The amps in, accordance with this invention may einploy frnercury, or any other metal, or amalgam, or alloy of metals or'any become vaporized atthe working temperature of the lamp, but for brevity of description we will presumethat mercury-is used.

According to this invention the lamp consists of, or com rises a chamber, for instant-c a tube, made 0 qu artz-glass or other suitable material, which tube is in communication with acontainer or containers, of mercury, which container or container-sis or are open at top, or only suiiiciently closed to exclude dirt, and are so arranged that, when the lamp is not in operation, the mercinry will brought into operation, and the requisite heat is supplied to the said tube, the mercury will vaporize in the said tube, and an arc will be formed, the vapor rcssing back the liquid mercury into the sair container, or containf ers, through openings so restricted that they will permit only slow passage of the mercury j therethrough,thus, prcserving'a steady are. The mercury will slowly i'eturn and fill the tube, again when the current is shut off from the lamp, andthus be in readiness to be brought againinto operation when required without the manipulation hitherto necessa to bring the mercury into the space in'whic it is Va orizedq I In t e accompanying drawings,

Figure 1 l Specification 0! Letters Patent.

vor holder. carries a hood 11', whlch carries supports 12 embracing the cups 2 and 3. The c cctrical Patented May 25, 1909.

1908. Serial No. 456,066. 4

f is a vertical section of a lamp embodying our invention in one form; Figs. 2, 3 and 4 are similar views of modified constructions of the tube portion.

Referring to Fig. 1, a tube 1 of quartz-- 1 glass has formed, or attached, at each turnedup end a cup (2 and 3) communicating with the tube 1 y contracted openings, orpasconsequently oi the arc),the said openings,

or passages, should not have a cross-sec-v t-ional area materially exceeding one twen'v' tieth of the cross-sectional area of the tube in which the arc is produced. A resistance wire 6, is arranged in any suitable manner, for instance wound around said tube 1 and a currentpasscd through the same to generate heat to eflcctlthc vaporization of mercury at the point required. tracted atjts midpart- 7 to receive the coils of the said resistance wire 6, so that it heats the tube 1 preferably midway between the on s' 2 and 3, and the respective ends of the to e 1. The terminals 8 and 9 of the electric conductors enter the rcs cctive cups 2 and 3 and are in contact witthe mercury thercin. The whole arrangement is supported in any suitable insulating body-part, As shown, the socket;piece 10 connections are )rcierably arranged as shown so that thc clcctric current passes first through the heating resistance 6 and thence to the terminal wire 8 in the mercury in the cup 2, and thcn (when the lamp is in operation.) through the mercury on one side and the vapor of mercury in the tube 1, and

through the mercury in the other side and in the cup 3, and out by the terminal wire 9,

which dips into the said mercury, all as indi- 100 cated by the arrows.

\lhcn the current is put on to the lamp,

vapor of mercury is, by the heat of the resistance 6, formed in the part of the tube 1 surrounded by the resistance, 'andthe arc acrossthe vapor emits-light, the pressure of the vapor forcing the liquid mercury toward each end of the tube 1, so that'the mercury slowly rises into the space in each cup (2 and 3), through the contracted openings, or passages, 4 and 5, forming the commumcatlons.

sages, 4 and 5, to keep the mercury steady The-tube 1 may be con' p the lamp.

ally some modifications.

between the cups 2 and 3 and the tube 1, these contracted passages thus giving steadiness of the arc. When the electric current is discontinued and the tube 1 is no longer sufficiently heated to vaporize mercury, the vapor condenses and the part of the tube 1 which was filled with vapor becomes again filled with liquid mercury ready for re-vaporizing and forming an are as before, when the electric current is again put on to light the lamp.

The on s 2 and 3 may be closed at top by any suitable meanssuihcient to exclude dirt,

but theyneed not be closed hermetically.

The resistance wire 6 may be of any suitable metal, or alloy, not readily oxidized when heated, for example iridio-platimun is a very suitable alloy.

Figs. 2, 3 and 4 illustrate diagrammatic- In these figures the parts which correspond with those shown in Fig. lare marked with the same reference numerals and the arrows indicate the direc-' tion of the current.

In Fig. 2 the terminal wires 8 and 9 pass through the contracted openings, or passages 4 and'5 so as to give the necessary very restricted passage-ways to and from the cups 2 and 3 without undue heating, the restriction of the passage-ways allowing but slow movement of the mercury and consequently keeping the incandescent vapor steady in the tube 1. In this figure the resistance wire 6 is shown coiled around an extension from the tube 1.

In Figs. 3 and 4 the ends of the tube 1 are enlarged at 13, and in these figures and in Fig. 2 the tube 1 is not contracted at its midpart.

In Fig. 4 is shown a means for short-circuiting the resistance wire 6 by bringing a by-pass wire 14 into the cup 3, to such a position that, when the mercury rises to any predetermined height in the said cup, the mercury makes contact with the said wire 14 and the current enters the mercury in the cup 3 Without first passing through the resistance wire 6.

If desired there maybe a piece of material 15 not acted upon by mercury, or other vaporizable' matter used (such as iridium, or

tantalum, for example), at one end, or at both ends, of the tube 1, as shown at one end in dotted lines in Fig. 3 to prevent vaporization of the mercury or the like, at that end, or those ends, interfering withthe action of We are aware that it has before been proposed to make vapor electric lamps with a tube heated by a wire coiled around it for the purpose of starting the lamp and having a receptacle for mercury at.eacl1 end and with means for cutting off the heating current when not required, and we do not claim such a resistance wound so as to heat the said tube together with electrical connections for passmgv a current oi electricity through the said resistance and the vaporizable material contained in the said tube, there being a space in each cup above the said material, so that when an electric currentis passed through the resistance and said material is in part vaporized, the un'vaporized portions of the same are in part forced through the contracted passages into the spaces in the said cups whereby unsteadiness of the arc is prevented and the return of said material to the tube is insured upon the cutting off of the electric current and the consequent condensation of the vapor formed, substantially as described.

2. In a vapor lamp of thetype described, a stationary vapor tube adapted to contain the material vaporized and a container located ahovesaid tube and communicating therewith bya constricted passage through which said material can be only slowly forced by the vapor generated during the operation of the lamp, whereby the arcis steadied, as described.

3. In a vapor lamp of the type described, a stationary vaporizing tube adapted to contain the material'vaporized and a container at atmospheric pressure located above said tube and communicating therewith by a constricted passage through which said material can beonly slowly forced by the vapor generated during the operation of the lamp, whereby the arc is steadied, as described.

In testimony whereof we have. signed our names to this specification in the presence of two subscribing witnesses.

HENRY ANDREW KENT. HAROLD GEORGE LACELL,

Witnesses THOMAS BREN'roN, ALBERT DAVIS. 

